The Monthly Microscopical Journal: Transactions of the Royal Microscopical Society, and Record of Histological Research at Home and Abroad, Volumen13

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Página 87 - G. fluviatilis, in the River Seine. 'Imagine an animal, like one of our autumnal spiders stationed at the centre of its well-spread net; imagine every thread of this net to be a living extension of the animal, elongating, branching, and becoming confluent so as to form a most intricate net...
Página 246 - Globigerina ooze, then, which it succeeds to the southward in a band apparently of no great width, the materials of this silicious deposit are derived entirely from the surface and intermediate depths. It is somewhat singular that Diatoms did not appear to be in such large numbers on the surface over the Diatom ooze as they were a little further north. This may perhaps be accounted for by our not having struck their...
Página 27 - In many cases the only tests that can be applied to distinguish between highly-altered ash-rock and a felstone are the presence of a bedded or fragmentary appearance on weathered surfaces, and the gradual passage into less altered and unmistakable ash. In the fourth division of his paper the author described some of the lavas and ashes of Cumberland of Lower Silurian age. With regard to these ancient lavas the following was given as a general definition : — The rock is generally of some shade of...
Página 245 - This, when examined under the microscope, was found to consist almost entirely of thefrustules of Diatoms, some of them wonderfully perfect in all the details of their ornament, and many of them broken up. The species of Diatoms entering into this deposit have not yet...
Página 27 - Pelsidolerites, answering in position to the modern Trachy-dolerites. A detailed examination of Cumbrian ash-rocks had convinced- the author that in many cases most intense metamorphism had taken place, that the finer ashy material had been partially melted down, and a kind of streaky flow caused around the larger fragments. There was every transition from an ash-rock in which a bedded or fragmentary structure was clearly visible, to an exceedingly close and flinty felstone-like rock, undistinguishable...
Página 213 - ... that neither by the microscope nor by any other means yet known to science, can the expert determine that a given stain is composed of human blood, and could not have been derived from any other source. This course is imperatively demanded of him by common honesty, without which scientific experts become more dangerous to society than the very criminals they are called upon to convict.
Página 253 - The principal red colouring-matter was connected with the hamoglobin of blood, and the two blue colouring matters were probably related to bile pigments ; but in both cases it was only a chemical and physical relationship, and the individual substances were quite distinct, and it seemed as though they were special secretions. There appeared to be no simple connection between the production of these various egg-pigments and the general...
Página 25 - This consists of a long cylindroid cell constricted at the middle and slightly expanded each side of the constriction. When the plant is about to duplicate itself, the cell-wall divides transversely at the constriction. From the open end of each half cell there protrudes a colorless mass of protoplasm defined by the primordial utricle.
Página 245 - Globigerincf, some of the tests and spicules of Radiolarians, and some sand particles ; but these foreign bodies were in too small proportion to affect the formation as consisting practically of Diatoms alone. On the 4th of February, in lat. 52°, 29...
Página 28 - ... nor the microscopic examination of thin slices, would in all cases enable truthful results to be arrived at, in discriminating between trap and altered ash-rocks ; but these methods and that of chemical analysis must be accompanied by oftentimes a laborious and detailed survey of the rocks in the open country, the various beds being traced out one by one and their weathered surfaces particularly noticed.

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